Influence of GM-CSF on ceramide pathway. (A) Intracellular ceramide variations measured at the peak of stimulation in KG1 cells treated with TNFα (20 ng/mL) and GM-CSF (13 ng/mL). Results are expressed as mean ± SD from 5 independent experiments. ^**P = .008. (B) KG1 cells were incubated with or without TNFα, C6-ceramide (10 μM), or GM-CSF for 2 hours. Transcripts of hTERT were quantified using the LightCycler TeloTAGGGhTERT quantification kit as previously described. Results are expressed as mean ± SD from 4 independent experiments. ^***P < .001; ^**P = .004.